
// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// Copyright (C) 2017 Gael Guennebaud <gael.guennebaud@inria.fr>
//
// This Source Code Form is subject to the terms of the Mozilla
// Public License v. 2.0. If a copy of the MPL was not distributed
// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.

#ifndef EIGEN_ARCH_CONJ_HELPER_H
#define EIGEN_ARCH_CONJ_HELPER_H

#define EIGEN_MAKE_CONJ_HELPER_CPLX_REAL(PACKET_CPLX, PACKET_REAL)                                                                                          \
    template <> struct conj_helper<PACKET_REAL, PACKET_CPLX, false, false>                                                                                  \
    {                                                                                                                                                       \
        EIGEN_STRONG_INLINE PACKET_CPLX pmadd(const PACKET_REAL& x, const PACKET_CPLX& y, const PACKET_CPLX& c) const { return padd(c, this->pmul(x, y)); } \
        EIGEN_STRONG_INLINE PACKET_CPLX pmul(const PACKET_REAL& x, const PACKET_CPLX& y) const                                                              \
        {                                                                                                                                                   \
            return PACKET_CPLX(Eigen::internal::pmul<PACKET_REAL>(x, y.v));                                                                                 \
        }                                                                                                                                                   \
    };                                                                                                                                                      \
                                                                                                                                                            \
    template <> struct conj_helper<PACKET_CPLX, PACKET_REAL, false, false>                                                                                  \
    {                                                                                                                                                       \
        EIGEN_STRONG_INLINE PACKET_CPLX pmadd(const PACKET_CPLX& x, const PACKET_REAL& y, const PACKET_CPLX& c) const { return padd(c, this->pmul(x, y)); } \
        EIGEN_STRONG_INLINE PACKET_CPLX pmul(const PACKET_CPLX& x, const PACKET_REAL& y) const                                                              \
        {                                                                                                                                                   \
            return PACKET_CPLX(Eigen::internal::pmul<PACKET_REAL>(x.v, y));                                                                                 \
        }                                                                                                                                                   \
    };

namespace Eigen {
namespace internal {

    template <bool Conjugate> struct conj_if;

    template <> struct conj_if<true>
    {
        template <typename T> EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE T operator()(const T& x) const { return numext::conj(x); }
        template <typename T> EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE T pconj(const T& x) const { return internal::pconj(x); }
    };

    template <> struct conj_if<false>
    {
        template <typename T> EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const T& operator()(const T& x) const { return x; }
        template <typename T> EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const T& pconj(const T& x) const { return x; }
    };

    // Generic Implementation, assume scalars since the packet-version is
    // specialized below.
    template <typename LhsType, typename RhsType, bool ConjLhs, bool ConjRhs> struct conj_helper
    {
        typedef typename ScalarBinaryOpTraits<LhsType, RhsType>::ReturnType ResultType;

        EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE ResultType pmadd(const LhsType& x, const RhsType& y, const ResultType& c) const { return this->pmul(x, y) + c; }

        EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE ResultType pmul(const LhsType& x, const RhsType& y) const
        {
            return conj_if<ConjLhs>()(x) * conj_if<ConjRhs>()(y);
        }
    };

    template <typename LhsScalar, typename RhsScalar> struct conj_helper<LhsScalar, RhsScalar, true, true>
    {
        typedef typename ScalarBinaryOpTraits<LhsScalar, RhsScalar>::ReturnType ResultType;

        EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE ResultType pmadd(const LhsScalar& x, const RhsScalar& y, const ResultType& c) const
        {
            return this->pmul(x, y) + c;
        }

        // We save a conjuation by using the identity conj(a)*conj(b) = conj(a*b).
        EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE ResultType pmul(const LhsScalar& x, const RhsScalar& y) const { return numext::conj(x * y); }
    };

    // Implementation with equal type, use packet operations.
    template <typename Packet, bool ConjLhs, bool ConjRhs> struct conj_helper<Packet, Packet, ConjLhs, ConjRhs>
    {
        typedef Packet ResultType;
        EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE Packet pmadd(const Packet& x, const Packet& y, const Packet& c) const
        {
            return Eigen::internal::pmadd(conj_if<ConjLhs>().pconj(x), conj_if<ConjRhs>().pconj(y), c);
        }

        EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE Packet pmul(const Packet& x, const Packet& y) const
        {
            return Eigen::internal::pmul(conj_if<ConjLhs>().pconj(x), conj_if<ConjRhs>().pconj(y));
        }
    };

    template <typename Packet> struct conj_helper<Packet, Packet, true, true>
    {
        typedef Packet ResultType;

        EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE Packet pmadd(const Packet& x, const Packet& y, const Packet& c) const
        {
            return Eigen::internal::pmadd(pconj(x), pconj(y), c);
        }
        // We save a conjuation by using the identity conj(a)*conj(b) = conj(a*b).
        EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE Packet pmul(const Packet& x, const Packet& y) const { return pconj(Eigen::internal::pmul(x, y)); }
    };

}  // namespace internal
}  // namespace Eigen

#endif  // EIGEN_ARCH_CONJ_HELPER_H
